Question

In a triangle PQR, ∠P +∠Q = 140 degree and ∠Q + ∠R = 70 degree, find P, Q and R.

Answer 1

<P + <Q = 140 degree .... (1)
we know
in triangle <P + <Q +<R = 180
thus
from (1)
140 + <R = 180
<R = 40 degree
Given <Q + <R = 70
putting value of <R we get
<Q + 40 = 70
<Q = 30 degree
Putting value of <Q in (1) we get
<P + 30 = 140
<P = 110 degree